Concerns about data falsification or fabrication in clinical trials have been heightened because of recent cases of improper conduct in the conduct of clinical trials. The objective of the study is to examine current practices, expert opinions, and case studies to develop statistical approaches for detecting fraud and to develop guidelines for the prevention and detection of fraud in clinical trials. The study has the following specific aims: 1. To describe quality assurance procedures currently used in clinical trials and their perceived utility in the prevention and detection of data falsification or fabrication 2. To do case studies of documented cases of data falsification or fabrication in clinical trials and to evaluate the potential impact on study findings 3. To study the extent to which data falsification or fabrication may be detected by statistical techniques and to evaluate the potential impact on study findings The specific aims will be accomplished by surveying directors of Coordinating Centers and Data and Safety Monitoring Committee members, studying Food and Drug Administration "for-cause" investigations and reports in scientific journals and newspapers, and examining clinical trials datasets, respectively.